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Feng L, Yan W, Tang X, Wu H, Pan Y, Lu D, Ling-Hu Q, Liu Y, Liu Y, Song X, Ali M, Fang L, Guo H, Li B. Multiple factors and features dictate the selective production of ct-siRNA in Arabidopsis. Commun Biol 2024; 7:474. [PMID: 38637717 PMCID: PMC11026412 DOI: 10.1038/s42003-024-06142-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Accepted: 04/03/2024] [Indexed: 04/20/2024] Open
Abstract
Coding transcript-derived siRNAs (ct-siRNAs) produced from specific endogenous loci can suppress the translation of their source genes to balance plant growth and stress response. In this study, we generated Arabidopsis mutants with deficiencies in RNA decay and/or post-transcriptional gene silencing (PTGS) pathways and performed comparative sRNA-seq analysis, revealing that multiple RNA decay and PTGS factors impede the ct-siRNA selective production. Genes that produce ct-siRNAs often show increased or unchanged expression and typically have higher GC content in sequence composition. The growth and development of plants can perturb the dynamic accumulation of ct-siRNAs from different gene loci. Two nitrate reductase genes, NIA1 and NIA2, produce massive amounts of 22-nt ct-siRNAs and are highly expressed in a subtype of mesophyll cells where DCL2 exhibits higher expression relative to DCL4, suggesting a potential role of cell-specific expression of ct-siRNAs. Overall, our findings unveil the multifaceted factors and features involved in the selective production and regulation of ct-siRNAs and enrich our understanding of gene silencing process in plants.
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Affiliation(s)
- Li Feng
- Peking University Institute of Advanced Agricultural Sciences, Shandong Laboratory of Advanced Agriculture Sciences in Weifang, Weifang, Shandong, 261325, China
| | - Wei Yan
- Institute of Plant and Food Science, Department of Biology, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - Xianli Tang
- Institute of Plant and Food Science, Department of Biology, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - Huihui Wu
- Institute of Plant and Food Science, Department of Biology, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - Yajie Pan
- Institute of Plant and Food Science, Department of Biology, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - Dongdong Lu
- Peking University Institute of Advanced Agricultural Sciences, Shandong Laboratory of Advanced Agriculture Sciences in Weifang, Weifang, Shandong, 261325, China
| | - Qianyan Ling-Hu
- Institute of Plant and Food Science, Department of Biology, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - Yuelin Liu
- Institute of Plant and Food Science, Department of Biology, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - Yongqi Liu
- Peking University Institute of Advanced Agricultural Sciences, Shandong Laboratory of Advanced Agriculture Sciences in Weifang, Weifang, Shandong, 261325, China
| | - Xiehai Song
- Peking University Institute of Advanced Agricultural Sciences, Shandong Laboratory of Advanced Agriculture Sciences in Weifang, Weifang, Shandong, 261325, China
| | - Muhammad Ali
- Peking University Institute of Advanced Agricultural Sciences, Shandong Laboratory of Advanced Agriculture Sciences in Weifang, Weifang, Shandong, 261325, China
| | - Liang Fang
- Institute of Plant and Food Science, Department of Biology, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - Hongwei Guo
- Institute of Plant and Food Science, Department of Biology, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China.
| | - Bosheng Li
- Peking University Institute of Advanced Agricultural Sciences, Shandong Laboratory of Advanced Agriculture Sciences in Weifang, Weifang, Shandong, 261325, China.
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2
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Xu C, Wang M, Cheng A, Yang Q, Huang J, Ou X, Sun D, He Y, Wu Z, Wu Y, Zhang S, Tian B, Zhao X, Liu M, Zhu D, Jia R, Chen S. Multiple functions of the nonstructural protein 3D in picornavirus infection. Front Immunol 2024; 15:1365521. [PMID: 38629064 PMCID: PMC11018997 DOI: 10.3389/fimmu.2024.1365521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Accepted: 03/21/2024] [Indexed: 04/19/2024] Open
Abstract
3D polymerase, also known as RNA-dependent RNA polymerase, is encoded by all known picornaviruses, and their structures are highly conserved. In the process of picornavirus replication, 3D polymerase facilitates the assembly of replication complexes and directly catalyzes the synthesis of viral RNA. The nuclear localization signal carried by picornavirus 3D polymerase, combined with its ability to interact with other viral proteins, viral RNA and cellular proteins, indicate that its noncatalytic role is equally important in viral infections. Recent studies have shown that 3D polymerase has multiple effects on host cell biological functions, including inducing cell cycle arrest, regulating host cell translation, inducing autophagy, evading immune responses, and triggering inflammasome formation. Thus, 3D polymerase would be a very valuable target for the development of antiviral therapies. This review summarizes current studies on the structure of 3D polymerase and its regulation of host cell responses, thereby improving the understanding of picornavirus-mediated pathogenesis caused by 3D polymerase.
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Affiliation(s)
- Chenxia Xu
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Mingshu Wang
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Anchun Cheng
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Qiao Yang
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Juan Huang
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Xumin Ou
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Di Sun
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Yu He
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Zhen Wu
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Ying Wu
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Shaqiu Zhang
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Bin Tian
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Xinxin Zhao
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Mafeng Liu
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Dekang Zhu
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Renyong Jia
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Shun Chen
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, China
- Institute of Veterinary Medicine and Immunology, Sichuan Agricultural University, Chengdu, China
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
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Ferrer-Orta C, Ferrero DS, Verdaguer N. Dual role of the foot-and-mouth disease virus 3B1 protein in the replication complex: As protein primer and as an essential component to recruit 3Dpol to membranes. PLoS Pathog 2023; 19:e1011373. [PMID: 37126532 PMCID: PMC10174528 DOI: 10.1371/journal.ppat.1011373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 05/11/2023] [Accepted: 04/18/2023] [Indexed: 05/02/2023] Open
Abstract
Picornavirus genome replication takes place in specialized intracellular membrane compartments that concentrate viral RNA and proteins as well as a number of host factors that also participate in the process. The core enzyme in the replication machinery is the viral RNA-dependent RNA polymerase (RdRP) 3Dpol. Replication requires the primer protein 3B (or VPg) attached to two uridine molecules. 3B uridylylation is also catalysed by 3Dpol. Another critical interaction in picornavirus replication is that between 3Dpol and the precursor 3AB, a membrane-binding protein responsible for the localization of 3Dpol to the membranous compartments at which replication occurs. Unlike other picornaviruses, the animal pathogen foot-and-mouth disease virus (FMDV), encodes three non-identical copies of the 3B (3B1, 3B2, and 3B3) that could be specialized in different functions within the replication complex. Here, we have used a combination of biophysics, molecular and structural biology approaches to characterize the functional binding of FMDV 3B1 to the base of the palm of 3Dpol. The 1.7 Å resolution crystal structure of the FMDV 3Dpol -3B1 complex shows that 3B1 simultaneously links two 3Dpol molecules by binding at the bottom of their palm subdomains in an almost symmetric way. The two 3B1 contact surfaces involve a combination of hydrophobic and basic residues at the N- (G5-P6, R9; Region I) and C-terminus (R16, L19-P20; Region II) of this small protein. Enzyme-Linked Immunosorbent Assays (ELISA) show that the two 3B1 binding sites play a role in 3Dpol binding, with region II presenting the highest affinity. ELISA assays show that 3Dpol has higher binding affinity for 3B1 than for 3B2 or 3B3. Membrane-based pull-down assays show that 3B1 region II, and to a lesser extent also region I play essential roles in mediating the interaction of 3AB with the polymerase and its recruitment to intracellular membranes.
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Affiliation(s)
- Cristina Ferrer-Orta
- Instituto de Biología Molecular de Barcelona. Consejo Superior de Investigaciones Científicas (IBMB-CSIC), Barcelona, Spain
| | - Diego S Ferrero
- Instituto de Biología Molecular de Barcelona. Consejo Superior de Investigaciones Científicas (IBMB-CSIC), Barcelona, Spain
| | - Nuria Verdaguer
- Instituto de Biología Molecular de Barcelona. Consejo Superior de Investigaciones Científicas (IBMB-CSIC), Barcelona, Spain
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4
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Higher-order structures of the foot-and-mouth disease virus RNA-dependent RNA polymerase required for genome replication. Commun Biol 2022; 5:61. [PMID: 35039618 PMCID: PMC8764057 DOI: 10.1038/s42003-021-02989-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 12/20/2021] [Indexed: 11/23/2022] Open
Abstract
Replication of many positive-sense RNA viruses occurs within intracellular membrane-associated compartments. These are thought to provide a favourable environment for replication to occur, concentrating essential viral structural and nonstructural components, as well as protecting these components from host-cell pathogen recognition and innate immune responses. However, the details of the molecular interactions and dynamics within these structures is very limited. One of the key components of the replication machinery is the RNA-dependent RNA polymerase, RdRp. This enzyme has been shown to form higher-order fibrils in vitro. Here, using the RdRp from foot-and-mouth disease virus (termed 3Dpol), we report fibril structures, solved at ~7-9 Å resolution by cryo-EM, revealing multiple conformations of a flexible assembly. Fitting high-resolution coordinates led to the definition of potential intermolecular interactions. We employed mutagenesis using a sub-genomic replicon system to probe the importance of these interactions for replication. We use these data to propose models for the role of higher-order 3Dpol complexes as a dynamic scaffold within which RNA replication can occur. Loundras et al. report on the fibril components of the RNA-dependent RNA polymerase RdRp from foot-and-mouth disease virus. They demonstrate that higher-order fibril-based interactions create multiple complex structures within which RNA replication can occur.
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5
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Ferrero DS, Falqui M, Verdaguer N. Snapshots of a Non-Canonical RdRP in Action. Viruses 2021; 13:v13071260. [PMID: 34203380 PMCID: PMC8310298 DOI: 10.3390/v13071260] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 06/24/2021] [Accepted: 06/25/2021] [Indexed: 11/17/2022] Open
Abstract
RNA viruses typically encode their own RNA-dependent RNA polymerase (RdRP) to ensure genome replication and transcription. The closed “right hand” architecture of RdRPs encircles seven conserved structural motifs (A to G) that regulate the polymerization activity. The four palm motifs, arranged in the sequential order A to D, are common to all known template dependent polynucleotide polymerases, with motifs A and C containing the catalytic aspartic acid residues. Exceptions to this design have been reported in members of the Permutotetraviridae and Birnaviridae families of positive single stranded (+ss) and double-stranded (ds) RNA viruses, respectively. In these enzymes, motif C is located upstream of motif A, displaying a permuted C–A–B–D connectivity. Here we study the details of the replication elongation process in the non-canonical RdRP of the Thosea asigna virus (TaV), an insect virus from the Permutatetraviridae family. We report the X-ray structures of three replicative complexes of the TaV polymerase obtained with an RNA template-primer in the absence and in the presence of incoming rNTPs. The structures captured different replication events and allowed to define the critical interactions involved in: (i) the positioning of the acceptor base of the template strand, (ii) the positioning of the 3’-OH group of the primer nucleotide during RNA replication and (iii) the recognition and positioning of the incoming nucleotide. Structural comparisons unveiled a closure of the active site on the RNA template-primer binding, before rNTP entry. This conformational rearrangement that also includes the repositioning of the motif A aspartate for the catalytic reaction to take place is maintained on rNTP and metal ion binding and after nucleotide incorporation, before translocation.
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Picarazzi F, Vicenti I, Saladini F, Zazzi M, Mori M. Targeting the RdRp of Emerging RNA Viruses: The Structure-Based Drug Design Challenge. Molecules 2020; 25:E5695. [PMID: 33287144 PMCID: PMC7730706 DOI: 10.3390/molecules25235695] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 11/30/2020] [Accepted: 12/01/2020] [Indexed: 02/06/2023] Open
Abstract
The RNA-dependent RNA polymerase (RdRp) is an essential enzyme for the viral replication process, catalyzing the viral RNA synthesis using a metal ion-dependent mechanism. In recent years, RdRp has emerged as an optimal target for the development of antiviral drugs, as demonstrated by recent approvals of sofosbuvir and remdesivir against Hepatitis C virus (HCV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), respectively. In this work, we overview the main sequence and structural features of the RdRp of emerging RNA viruses such as Coronaviruses, Flaviviruses, and HCV, as well as inhibition strategies implemented so far. While analyzing the structural information available on the RdRp of emerging RNA viruses, we provide examples of success stories such as for HCV and SARS-CoV-2. In contrast, Flaviviruses' story has raised attention about how the lack of structural details on catalytically-competent or ligand-bound RdRp strongly hampers the application of structure-based drug design, either in repurposing and conventional approaches.
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Affiliation(s)
- Francesca Picarazzi
- Department of Biotechnology, Chemistry and Pharmacy, Department of Excellence 2018–2022, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy;
| | - Ilaria Vicenti
- Department of Medical Biotechnologies, University of Siena, 53100 Siena, Italy; (I.V.); (F.S.); (M.Z.)
| | - Francesco Saladini
- Department of Medical Biotechnologies, University of Siena, 53100 Siena, Italy; (I.V.); (F.S.); (M.Z.)
| | - Maurizio Zazzi
- Department of Medical Biotechnologies, University of Siena, 53100 Siena, Italy; (I.V.); (F.S.); (M.Z.)
| | - Mattia Mori
- Department of Biotechnology, Chemistry and Pharmacy, Department of Excellence 2018–2022, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy;
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Residues within the Foot-and-Mouth Disease Virus 3D pol Nuclear Localization Signal Affect Polymerase Fidelity. J Virol 2020; 94:JVI.00833-20. [PMID: 32581111 DOI: 10.1128/jvi.00833-20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 06/11/2020] [Indexed: 11/20/2022] Open
Abstract
Many RNA viruses encode a proof-reading deficient, low-fidelity RNA-dependent polymerase (RdRp), which generates genetically diverse populations that can adapt to changing environments and thwart antiviral therapies. 3Dpol, the RdRp of the foot-and-mouth disease virus (FMDV), is responsible for replication of viral genomes. The 3Dpol N terminus encodes a nuclear localization signal (NLS) sequence,MRKTKLAPT, important for import of the protein to host nucleus. Previous studies showed that substitutions at residues 18 and 20 of the NLS are defective in proper incorporation of nucleotides and RNA binding. Here, we use a systematic alanine scanning mutagenesis approach to understand the role of individual residues of the NLS in nuclear localization and nucleotide incorporation activities of 3Dpol We identify two residues of 3Dpol NLS, T19 and L21, that are important for the maintenance of enzyme fidelity. The 3Dpol NLS alanine substitutions of T19 and L21 results in aberrant incorporation of nucleoside analogs, conferring a low fidelity phenotype of the enzyme. A molecular dynamics simulation of RNA- and mutagen (RTP)-bound 3Dpol revealed that the T19 residue participates in a hydrogen bond network, including D165 in motif F and R416 at the C terminus of the FMDV 3Dpol and RNA template-primer. Based on these findings and previous studies, we conclude that at least the first six residues of theMRKTKLAPT sequence motif play a vital role in the maintenance of faithful RNA synthesis activity (fidelity) of FMDV 3Dpol, suggesting that the role of the NLS motif in similar viral polymerases needs to be revisited.IMPORTANCE In this study, we employed genetic and molecular dynamics approaches to analyze the role of individual amino acids of the FMDV 3Dpol nuclear localization signal (NLS). The NLS residues were mutated to alanine using a type A full-genome cDNA clone, and the virus progeny was analyzed for defects in growth and in competition with the parental virus. We identified two mutants in 3Dpol, T19A and L21A, that exhibited high rate of mutation, were sensitive to nucleotide analogs, and displayed reduced replicative fitness compared to the parental virus. Using molecular dynamics simulation, we demonstrated that residues T19 and L21 played a role in the structural configuration of the interaction network at the 3Dpol palm subdomain. Cumulatively, our data suggest that the T19 and L21 3Dpol amino acids are important for maintaining the fidelity of the FMDV polymerase and ensuring faithful replication of the FMDV genome.
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Wang H, Xin X, Zheng C, Shen C. Single-Cell Analysis of Foot-and-Mouth Disease Virus. Front Microbiol 2020; 11:361. [PMID: 32194538 PMCID: PMC7066083 DOI: 10.3389/fmicb.2020.00361] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 02/18/2020] [Indexed: 11/25/2022] Open
Abstract
With the rapid development of single-cell technologies, the mechanisms underlying viral infections and the interactions between hosts and viruses are starting to be explored at the single-cell level. The foot-and-mouth-disease (FMD) virus (FMDV) causes an acute and persistent infection that can result in the break-out of FMD, which can have serious effects on animal husbandry. Single-cell techniques have emerged as powerful approaches to analyze virus infection at the resolution of individual cells. In this review, the existing single-cell studies examining FMDV will be systematically summarized, and the central themes of these studies will be presented.
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Affiliation(s)
- Hailong Wang
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
- Center for Experimental Medicine, The First Affiliated Hospital of Nanchang University, Nanchang, China
| | - Xiu Xin
- Institute of Pathogenic Microorganism and College of Bioscience and Engineering, Jiangxi Agricultural University, Nanchang, China
| | - Congyi Zheng
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
- China Center for Type Culture Collection, Wuhan University, Wuhan, China
| | - Chao Shen
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
- China Center for Type Culture Collection, Wuhan University, Wuhan, China
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Abstract
Genetic variation is a necessity of all biological systems. Viruses use all known mechanisms of variation; mutation, several forms of recombination, and segment reassortment in the case of viruses with a segmented genome. These processes are intimately connected with the replicative machineries of viruses, as well as with fundamental physical-chemical properties of nucleotides when acting as template or substrate residues. Recombination has been viewed as a means to rescue viable genomes from unfit parents or to produce large modifications for the exploration of phenotypic novelty. All types of genetic variation can act conjointly as blind processes to provide the raw materials for adaptation to the changing environments in which viruses must replicate. A distinction is made between mechanistically unavoidable and evolutionarily relevant mutation and recombination.
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10
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Russo AG, Eden JS, Enosi Tuipulotu D, Shi M, Selechnik D, Shine R, Rollins LA, Holmes EC, White PA. Viral Discovery in the Invasive Australian Cane Toad ( Rhinella marina) Using Metatranscriptomic and Genomic Approaches. J Virol 2018; 92:JVI.00768-18. [PMID: 29899109 PMCID: PMC6096826 DOI: 10.1128/jvi.00768-18] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Accepted: 06/07/2018] [Indexed: 12/19/2022] Open
Abstract
Cane toads are poisonous amphibians that were introduced to Australia in 1935 for insect control. Since then, their population has increased dramatically, and they now threaten many native Australian species. One potential method to control the population is to release a cane toad virus with high mortality rates, yet few cane toad viruses have been characterized. This study samples cane toads from different Australian locations and uses an RNA sequencing and computational approach to find new viruses. We report novel complete picornavirus and retrovirus sequences that were genetically similar to viruses infecting frogs, reptiles, and fish. Using data generated in other studies, we show that these viral sequences are present in cane toads from distinct Australian locations. Three sequences related to circoviruses were also found in the toad genome. The identification of new viral sequences will aid future studies that investigate their prevalence and potential as agents for biocontrol. Cane toads are a notorious invasive species, inhabiting over 1.2 million km2 of Australia and threatening native biodiversity. The release of pathogenic cane toad viruses is one possible biocontrol strategy yet is currently hindered by the poorly described cane toad virome. Metatranscriptomic analysis of 16 cane toad livers revealed the presence of a novel and full-length picornavirus, Rhimavirus A (RhiV-A), a member of a reptile- and amphibian-specific cluster of the Picornaviridae basal to the Kobuvirus-like group. In the combined liver transcriptome, we also identified a complete genome sequence of a distinct epsilonretrovirus, Rhinella marina endogenous retrovirus (RMERV). The recently sequenced cane toad genome contains 8 complete RMERV proviruses as well as 21 additional truncated insertions. The oldest full-length RMERV provirus was estimated to have inserted 1.9 million years ago (MYA). To screen for these viral sequences in additional toads, we analyzed publicly available transcriptomes from six diverse Australian locations. RhiV-A transcripts were identified in toads sampled from three locations across 1,000 km of Australia, stretching to the current Western Australia (WA) invasion front, while RMERV transcripts were observed at all six sites. Finally, we scanned the cane toad genome for nonretroviral endogenous viral elements, finding three sequences related to small DNA viruses in the family Circoviridae. This shows ancestral circoviral infection with subsequent genomic integration. The identification of these current and past viral infections enriches our knowledge of the cane toad virome, an understanding of which will facilitate future work on infection and disease in this important invasive species. IMPORTANCE Cane toads are poisonous amphibians that were introduced to Australia in 1935 for insect control. Since then, their population has increased dramatically, and they now threaten many native Australian species. One potential method to control the population is to release a cane toad virus with high mortality rates, yet few cane toad viruses have been characterized. This study samples cane toads from different Australian locations and uses an RNA sequencing and computational approach to find new viruses. We report novel complete picornavirus and retrovirus sequences that were genetically similar to viruses infecting frogs, reptiles, and fish. Using data generated in other studies, we show that these viral sequences are present in cane toads from distinct Australian locations. Three sequences related to circoviruses were also found in the toad genome. The identification of new viral sequences will aid future studies that investigate their prevalence and potential as agents for biocontrol.
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Affiliation(s)
- Alice G. Russo
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - John-Sebastian Eden
- Marie Bashir Institute for Infectious Disease and Biosecurity, School of Life and Environmental Sciences and Sydney Medical School, Charles Perkins Centre, The University of Sydney, Sydney, New South Wales, Australia
- The Westmead Institute of Medical Research, Centre for Virus Research, Westmead, NSW, Australia
| | - Daniel Enosi Tuipulotu
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Mang Shi
- Marie Bashir Institute for Infectious Disease and Biosecurity, School of Life and Environmental Sciences and Sydney Medical School, Charles Perkins Centre, The University of Sydney, Sydney, New South Wales, Australia
| | - Daniel Selechnik
- School of Life and Environmental Sciences, The University of Sydney, Sydney, New South Wales, Australia
| | - Richard Shine
- School of Life and Environmental Sciences, The University of Sydney, Sydney, New South Wales, Australia
| | - Lee Ann Rollins
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Geelong, Victoria, Australia
- Evolution and Ecology Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Edward C. Holmes
- Marie Bashir Institute for Infectious Disease and Biosecurity, School of Life and Environmental Sciences and Sydney Medical School, Charles Perkins Centre, The University of Sydney, Sydney, New South Wales, Australia
| | - Peter A. White
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales, Australia
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11
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Herod MR, Gold S, Lasecka-Dykes L, Wright C, Ward JC, McLean TC, Forrest S, Jackson T, Tuthill TJ, Rowlands DJ, Stonehouse NJ. Genetic economy in picornaviruses: Foot-and-mouth disease virus replication exploits alternative precursor cleavage pathways. PLoS Pathog 2017; 13:e1006666. [PMID: 28968463 PMCID: PMC5638621 DOI: 10.1371/journal.ppat.1006666] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 10/12/2017] [Accepted: 09/25/2017] [Indexed: 12/20/2022] Open
Abstract
The RNA genomes of picornaviruses are translated into single polyproteins which are subsequently cleaved into structural and non-structural protein products. For genetic economy, proteins and processing intermediates have evolved to perform distinct functions. The picornavirus precursor protein, P3, is cleaved to produce membrane-associated 3A, primer peptide 3B, protease 3Cpro and polymerase 3Dpol. Uniquely, foot-and-mouth disease virus (FMDV) encodes three similar copies of 3B (3B1-3), thus providing a convenient natural system to explore the role(s) of 3B in the processing cascade. Using a replicon system, we confirmed by genetic deletion or functional inactivation that each copy of 3B appears to function independently to prime FMDV RNA replication. However, we also show that deletion of 3B3 prevents replication and that this could be reversed by introducing mutations at the C-terminus of 3B2 that restored the natural sequence at the 3B3-3C cleavage site. In vitro translation studies showed that precursors with 3B3 deleted were rapidly cleaved to produce 3CD but that no polymerase, 3Dpol, was detected. Complementation assays, using distinguishable replicons bearing different inactivating mutations, showed that replicons with mutations within 3Dpol could be recovered by 3Dpol derived from "helper" replicons (incorporating inactivation mutations in all three copies of 3B). However, complementation was not observed when the natural 3B-3C cleavage site was altered in the "helper" replicon, again suggesting that a processing abnormality at this position prevented the production of 3Dpol. When mutations affecting polyprotein processing were introduced into an infectious clone, viable viruses were recovered but these had acquired compensatory mutations in the 3B-3C cleavage site. These mutations were shown to restore the wild-type processing characteristics when analysed in an in vitro processing assay. Overall, this study demonstrates a dual functional role of the small primer peptide 3B3, further highlighting how picornaviruses increase genetic economy.
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Affiliation(s)
- Morgan R. Herod
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Sarah Gold
- The Pirbright Institute, Pirbright, Surrey, United Kingdom
| | | | | | - Joseph C. Ward
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Thomas C. McLean
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Sophie Forrest
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Terry Jackson
- The Pirbright Institute, Pirbright, Surrey, United Kingdom
| | | | - David J. Rowlands
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Nicola J. Stonehouse
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
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12
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Understanding the Mechanism of the Broad-Spectrum Antiviral Activity of Favipiravir (T-705): Key Role of the F1 Motif of the Viral Polymerase. J Virol 2017; 91:JVI.00487-17. [PMID: 28381577 DOI: 10.1128/jvi.00487-17] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2017] [Accepted: 03/28/2017] [Indexed: 01/10/2023] Open
Abstract
Favipiravir (T-705) is a broad-spectrum antiviral agent that has been approved in Japan for the treatment of influenza virus infections. T-705 also inhibits the replication of various RNA viruses, including chikungunya virus (CHIKV). We demonstrated earlier that the K291R mutation in the F1 motif of the RNA-dependent RNA polymerase (RdRp) of CHIKV is responsible for low-level resistance to T-705. Interestingly, this lysine is highly conserved in the RdRp of positive-sense single-stranded RNA (+ssRNA) viruses. To obtain insights into the unique broad-spectrum antiviral activity of T-705, we explored the role of this lysine using another +ssRNA virus, namely, coxsackievirus B3 (CVB3). Introduction of the corresponding K-to-R substitution in the CVB3 RdRp (K159R) resulted in a nonviable virus. Replication competence of the K159R variant was restored by spontaneous acquisition of an A239G substitution in the RdRp. A mutagenesis analysis at position K159 identified the K159M variant as the only other viable variant which had also acquired the A239G substitution. The K159 substitutions markedly decreased the processivity of the purified viral RdRp, which was restored by the introduction of the A239G mutation. The K159R A239G and K159M A239G variants proved, surprisingly, more susceptible than the wild-type virus to T-705 and exhibited lower fidelity in polymerase assays. Furthermore, the K159R A239G variant was found to be highly attenuated in mice. We thus demonstrate that the conserved lysine in the F1 motif of the RdRp of +ssRNA viruses is involved in the broad-spectrum antiviral activity of T-705 and that it is a key amino acid for the proper functioning of the enzyme.IMPORTANCE In this study, we report the key role of a highly conserved lysine residue of the viral polymerase in the broad-spectrum antiviral activity of favipiravir (T-705) against positive-sense single-stranded RNA viruses. Substitutions of this conserved lysine have a major negative impact on the functionality of the RdRp. Furthermore, we show that this lysine is involved in the fidelity of the RdRp and that the RdRp fidelity influences the sensitivity of the virus for the antiviral efficacy of T-705. Consequently, these results provide insights into the mechanism of the antiviral activity of T-705 and may lay the basis for the design of novel chemical scaffolds that may be endowed with a more potent broad-spectrum antiviral activity than that of T-705.
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13
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Both cis and trans Activities of Foot-and-Mouth Disease Virus 3D Polymerase Are Essential for Viral RNA Replication. J Virol 2016; 90:6864-6883. [PMID: 27194768 PMCID: PMC4944275 DOI: 10.1128/jvi.00469-16] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 05/11/2016] [Indexed: 11/20/2022] Open
Abstract
The Picornaviridae is a large family of positive-sense RNA viruses that contains numerous human and animal pathogens, including foot-and-mouth disease virus (FMDV). The picornavirus replication complex comprises a coordinated network of protein-protein and protein-RNA interactions involving multiple viral and host-cellular factors. Many of the proteins within the complex possess multiple roles in viral RNA replication, some of which can be provided in trans (i.e., via expression from a separate RNA molecule), while others are required in cis (i.e., expressed from the template RNA molecule). In vitro studies have suggested that multiple copies of the RNA-dependent RNA polymerase (RdRp) 3D are involved in the viral replication complex. However, it is not clear whether all these molecules are catalytically active or what other function(s) they provide. In this study, we aimed to distinguish between catalytically active 3D molecules and those that build a replication complex. We report a novel nonenzymatic cis-acting function of 3D that is essential for viral-genome replication. Using an FMDV replicon in complementation experiments, our data demonstrate that this cis-acting role of 3D is distinct from the catalytic activity, which is predominantly trans acting. Immunofluorescence studies suggest that both cis- and trans-acting 3D molecules localize to the same cellular compartment. However, our genetic and structural data suggest that 3D interacts in cis with RNA stem-loops that are essential for viral RNA replication. This study identifies a previously undescribed aspect of picornavirus replication complex structure-function and an important methodology for probing such interactions further. IMPORTANCE Foot-and-mouth disease virus (FMDV) is an important animal pathogen responsible for foot-and-mouth disease. The disease is endemic in many parts of the world with outbreaks within livestock resulting in major economic losses. Propagation of the viral genome occurs within replication complexes, and understanding this process can facilitate the development of novel therapeutic strategies. Many of the nonstructural proteins involved in replication possess multiple functions in the viral life cycle, some of which can be supplied to the replication complex from a separate genome (i.e., in trans) while others must originate from the template (i.e., in cis). Here, we present an analysis of cis and trans activities of the RNA-dependent RNA polymerase 3D. We demonstrate a novel cis-acting role of 3D in replication. Our data suggest that this role is distinct from its enzymatic functions and requires interaction with the viral genome. Our data further the understanding of genome replication of this important pathogen.
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14
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Herod MR, Loundras EA, Ward JC, Tulloch F, Rowlands DJ, Stonehouse NJ. Employing transposon mutagenesis to investigate foot-and-mouth disease virus replication. J Gen Virol 2016; 96:3507-3518. [PMID: 26432090 DOI: 10.1099/jgv.0.000306] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Probing the molecular interactions within the foot-and-mouth disease virus (FMDV) RNA replication complex has been restricted in part by the lack of suitable reagents. Random insertional mutagenesis has proven an excellent method to reveal domains of proteins essential for virus replication as well as locations that can tolerate small genetic insertions. Such insertion sites can subsequently be adapted by the incorporation of commonly used epitope tags, facilitating their detection with commercially available reagents. In this study, we used random transposon-mediated mutagenesis to produce a library of 15 nt insertions in the FMDV nonstructural polyprotein. Using a replicon-based assay, we isolated multiple replication-competent as well as replication-defective insertions. We adapted the replication-competent insertion sites for the successful incorporation of epitope tags within FMDV non-structural proteins for use in a variety of downstream assays. Additionally, we showed that replication of some of the replication-defective insertion mutants could be rescued by co-transfection of a ‘helper’ replicon, demonstrating a novel use of random mutagenesis to identify intergenomic trans-complementation. Both the epitope tags and replication-defective insertions identified here will be valuable tools for probing interactions within picornavirus replication complexes.
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Affiliation(s)
- Morgan R Herod
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
| | - Eleni-Anna Loundras
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
| | - Joseph C Ward
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
| | - Fiona Tulloch
- Biomedical Sciences Research Complex (BSRC), School of Biology, University of St Andrews, North Haugh, St Andrews, KY16 9ST, UK
| | - David J Rowlands
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
| | - Nicola J Stonehouse
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
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15
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Domingo E. Molecular Basis of Genetic Variation of Viruses. VIRUS AS POPULATIONS 2016. [PMCID: PMC7149591 DOI: 10.1016/b978-0-12-800837-9.00002-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Genetic variation is a necessity of all biological systems. Viruses use all known mechanisms of variation: mutation, several forms of recombination, and segment reassortment in the case of viruses with a segmented genome. These processes are intimately connected with the replicative machineries of viruses, as well as with fundamental physico-chemical properties of nucleotides when acting as template or substrate residues. Recombination has been viewed as a means to rescue viable genomes from unfit parents, or to produce large modifications for the exploration of phenotypic novelty. All types of genetic variation can act conjointly as blind processes to provide the raw materials for adaptation to the changing environments in which viruses must replicate.
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16
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Perales C, Quer J, Gregori J, Esteban JI, Domingo E. Resistance of Hepatitis C Virus to Inhibitors: Complexity and Clinical Implications. Viruses 2015; 7:5746-66. [PMID: 26561827 PMCID: PMC4664975 DOI: 10.3390/v7112902] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Revised: 10/23/2015] [Accepted: 10/26/2015] [Indexed: 12/20/2022] Open
Abstract
Selection of inhibitor-resistant viral mutants is universal for viruses that display quasi-species dynamics, and hepatitis C virus (HCV) is no exception. Here we review recent results on drug resistance in HCV, with emphasis on resistance to the newly-developed, directly-acting antiviral agents, as they are increasingly employed in the clinic. We put the experimental observations in the context of quasi-species dynamics, in particular what the genetic and phenotypic barriers to resistance mean in terms of exploration of sequence space while HCV replicates in the liver of infected patients or in cell culture. Strategies to diminish the probability of viral breakthrough during treatment are briefly outlined.
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Affiliation(s)
- Celia Perales
- Liver Unit, Internal Medicine, Laboratory of Malalties Hepàtiques, Vall d'Hebron Institut de Recerca-Hospital Universitari Vall d'Hebron (VHIR-HUVH), Universitat Autònoma de Barcelona, 08035 Barcelona, Spain.
- Centro de Biologia Molecular "Severo Ochoa" (CSIC-UAM), Cantoblanco, 28049 Madrid, Spain.
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), 08035 Barcelona, Spain.
| | - Josep Quer
- Liver Unit, Internal Medicine, Laboratory of Malalties Hepàtiques, Vall d'Hebron Institut de Recerca-Hospital Universitari Vall d'Hebron (VHIR-HUVH), Universitat Autònoma de Barcelona, 08035 Barcelona, Spain.
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), 08035 Barcelona, Spain.
- Universitat Autònoma de Barcelona, Bellaterra 08193, Spain.
| | - Josep Gregori
- Liver Unit, Internal Medicine, Laboratory of Malalties Hepàtiques, Vall d'Hebron Institut de Recerca-Hospital Universitari Vall d'Hebron (VHIR-HUVH), Universitat Autònoma de Barcelona, 08035 Barcelona, Spain.
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), 08035 Barcelona, Spain.
- Roche Diagnostics SL, 08174 Sant Cugat del Vallès, Spain.
| | - Juan Ignacio Esteban
- Liver Unit, Internal Medicine, Laboratory of Malalties Hepàtiques, Vall d'Hebron Institut de Recerca-Hospital Universitari Vall d'Hebron (VHIR-HUVH), Universitat Autònoma de Barcelona, 08035 Barcelona, Spain.
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), 08035 Barcelona, Spain.
- Universitat Autònoma de Barcelona, Bellaterra 08193, Spain.
| | - Esteban Domingo
- Centro de Biologia Molecular "Severo Ochoa" (CSIC-UAM), Cantoblanco, 28049 Madrid, Spain.
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), 08035 Barcelona, Spain.
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17
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RNA-Dependent RNA Polymerases of Picornaviruses: From the Structure to Regulatory Mechanisms. Viruses 2015; 7:4438-60. [PMID: 26258787 PMCID: PMC4576190 DOI: 10.3390/v7082829] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Revised: 07/24/2015] [Accepted: 07/29/2015] [Indexed: 12/25/2022] Open
Abstract
RNA viruses typically encode their own RNA-dependent RNA polymerase (RdRP) to ensure genome replication within the infected cells. RdRP function is critical not only for the virus life cycle but also for its adaptive potential. The combination of low fidelity of replication and the absence of proofreading and excision activities within the RdRPs result in high mutation frequencies that allow these viruses a rapid adaptation to changing environments. In this review, we summarize the current knowledge about structural and functional aspects on RdRP catalytic complexes, focused mainly in the Picornaviridae family. The structural data currently available from these viruses provided high-resolution snapshots for a range of conformational states associated to RNA template-primer binding, rNTP recognition, catalysis and chain translocation. As these enzymes are major targets for the development of antiviral compounds, such structural information is essential for the design of new therapies.
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18
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Multifunctionality of a picornavirus polymerase domain: nuclear localization signal and nucleotide recognition. J Virol 2015; 89:6848-59. [PMID: 25903341 DOI: 10.1128/jvi.03283-14] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Accepted: 04/13/2015] [Indexed: 01/18/2023] Open
Abstract
UNLABELLED The N-terminal region of the foot-and-mouth disease virus (FMDV) 3D polymerase contains the sequence MRKTKLAPT (residues 16 to 24) that acts as a nuclear localization signal. A previous study showed that substitutions K18E and K20E diminished the transport to the nucleus of 3D and 3CD and severely impaired virus infectivity. These residues have also been implicated in template binding, as seen in the crystal structures of different 3D-RNA elongation complexes. Here, we report the biochemical and structural characterization of different mutant polymerases harboring substitutions at residues 18 and 20, in particular, K18E, K18A, K20E, K20A, and the double mutant K18A K20A (KAKA). All mutant enzymes exhibit low RNA binding activity, low processivity, and alterations in nucleotide recognition, including increased incorporation of ribavirin monophosphate (RMP) relative to the incorporation of cognate nucleotides compared with the wild-type enzyme. The structural analysis shows an unprecedented flexibility of the 3D mutant polymerases, including both global rearrangements of the closed-hand architecture and local conformational changes at loop β9-α11 (within the polymerase motif B) and at the template-binding channel. Specifically, in 3D bound to RNA, both K18E and K20E induced the opening of new pockets in the template channel where the downstream templating nucleotide at position +2 binds. The comparisons of free and RNA-bound enzymes suggest that the structural rearrangements may occur in a concerted mode to regulate RNA replication, processivity, and fidelity. Thus, the N-terminal region of FMDV 3D that acts as a nuclear localization signal (NLS) and in template binding is also involved in nucleotide recognition and can affect the incorporation of nucleotide analogues. IMPORTANCE The study documents multifunctionality of a nuclear localization signal (NLS) located at the N-terminal region of the foot-and-mouth disease viral polymerase (3D). Amino acid substitutions at this polymerase region can impair the transport of 3D to the nucleus, reduce 3D binding to RNA, and alter the relative incorporation of standard nucleoside monophosphate versus ribavirin monophosphate. Structural data reveal that the conformational changes in this region, forming part of the template channel entry, would be involved in nucleotide discrimination. The results have implications for the understanding of viral polymerase function and for lethal mutagenesis mechanisms.
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van der Linden L, Vives-Adrián L, Selisko B, Ferrer-Orta C, Liu X, Lanke K, Ulferts R, De Palma AM, Tanchis F, Goris N, Lefebvre D, De Clercq K, Leyssen P, Lacroix C, Pürstinger G, Coutard B, Canard B, Boehr DD, Arnold JJ, Cameron CE, Verdaguer N, Neyts J, van Kuppeveld FJM. The RNA template channel of the RNA-dependent RNA polymerase as a target for development of antiviral therapy of multiple genera within a virus family. PLoS Pathog 2015; 11:e1004733. [PMID: 25799064 PMCID: PMC4370873 DOI: 10.1371/journal.ppat.1004733] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2014] [Accepted: 02/06/2015] [Indexed: 01/08/2023] Open
Abstract
The genus Enterovirus of the family Picornaviridae contains many important human pathogens (e.g., poliovirus, coxsackievirus, rhinovirus, and enterovirus 71) for which no antiviral drugs are available. The viral RNA-dependent RNA polymerase is an attractive target for antiviral therapy. Nucleoside-based inhibitors have broad-spectrum activity but often exhibit off-target effects. Most non-nucleoside inhibitors (NNIs) target surface cavities, which are structurally more flexible than the nucleotide-binding pocket, and hence have a more narrow spectrum of activity and are more prone to resistance development. Here, we report a novel NNI, GPC-N114 (2,2'-[(4-chloro-1,2-phenylene)bis(oxy)]bis(5-nitro-benzonitrile)) with broad-spectrum activity against enteroviruses and cardioviruses (another genus in the picornavirus family). Surprisingly, coxsackievirus B3 (CVB3) and poliovirus displayed a high genetic barrier to resistance against GPC-N114. By contrast, EMCV, a cardiovirus, rapidly acquired resistance due to mutations in 3Dpol. In vitro polymerase activity assays showed that GPC-N114 i) inhibited the elongation activity of recombinant CVB3 and EMCV 3Dpol, (ii) had reduced activity against EMCV 3Dpol with the resistance mutations, and (iii) was most efficient in inhibiting 3Dpol when added before the RNA template-primer duplex. Elucidation of a crystal structure of the inhibitor bound to CVB3 3Dpol confirmed the RNA-binding channel as the target for GPC-N114. Docking studies of the compound into the crystal structures of the compound-resistant EMCV 3Dpol mutants suggested that the resistant phenotype is due to subtle changes that interfere with the binding of GPC-N114 but not of the RNA template-primer. In conclusion, this study presents the first NNI that targets the RNA template channel of the picornavirus polymerase and identifies a new pocket that can be used for the design of broad-spectrum inhibitors. Moreover, this study provides important new insight into the plasticity of picornavirus polymerases at the template binding site.
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Affiliation(s)
- Lonneke van der Linden
- Department of Medical Microbiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Centre, Nijmegen, The Netherlands
- Laboratory of Virology and Chemotherapy, Rega Institute for Medical Research, University of Leuven, Leuven, Belgium
| | - Laia Vives-Adrián
- Institut de Biologia Molecular de Barcelona (CSIC), Parc Científic de Barcelona, Barcelona, Spain
| | - Barbara Selisko
- AFMB UMR 7257, Aix-Marseille Université & CNRS, Marseille, France
| | - Cristina Ferrer-Orta
- Institut de Biologia Molecular de Barcelona (CSIC), Parc Científic de Barcelona, Barcelona, Spain
| | - Xinran Liu
- Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Kjerstin Lanke
- Department of Medical Microbiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Rachel Ulferts
- Department of Medical Microbiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Centre, Nijmegen, The Netherlands
- Virology Division, Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Armando M. De Palma
- Laboratory of Virology and Chemotherapy, Rega Institute for Medical Research, University of Leuven, Leuven, Belgium
| | - Federica Tanchis
- Abteilung Pharmazeutische Chemie, Institut für Pharmazie, Universität Innsbruck, Innsbruck, Austria
| | | | - David Lefebvre
- Unit of Vesicular and Exotic Diseases, Virology Department, CODA-CERVA, Veterinary and Agrochemical Research Centre, Brussels, Belgium
| | - Kris De Clercq
- Unit of Vesicular and Exotic Diseases, Virology Department, CODA-CERVA, Veterinary and Agrochemical Research Centre, Brussels, Belgium
| | - Pieter Leyssen
- Laboratory of Virology and Chemotherapy, Rega Institute for Medical Research, University of Leuven, Leuven, Belgium
| | - Céline Lacroix
- Laboratory of Virology and Chemotherapy, Rega Institute for Medical Research, University of Leuven, Leuven, Belgium
| | - Gerhard Pürstinger
- Abteilung Pharmazeutische Chemie, Institut für Pharmazie, Universität Innsbruck, Innsbruck, Austria
| | - Bruno Coutard
- AFMB UMR 7257, Aix-Marseille Université & CNRS, Marseille, France
| | - Bruno Canard
- AFMB UMR 7257, Aix-Marseille Université & CNRS, Marseille, France
| | - David D. Boehr
- Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Jamie J. Arnold
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Craig E. Cameron
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Nuria Verdaguer
- Institut de Biologia Molecular de Barcelona (CSIC), Parc Científic de Barcelona, Barcelona, Spain
| | - Johan Neyts
- Laboratory of Virology and Chemotherapy, Rega Institute for Medical Research, University of Leuven, Leuven, Belgium
| | - Frank J. M. van Kuppeveld
- Department of Medical Microbiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Centre, Nijmegen, The Netherlands
- Virology Division, Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
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Mollaie HR, Monavari SHR, Arabzadeh SAM, Shamsi-Shahrabadi M, Fazlalipour M, Afshar RM. RNAi and miRNA in viral infections and cancers. Asian Pac J Cancer Prev 2015; 14:7045-56. [PMID: 24460249 DOI: 10.7314/apjcp.2013.14.12.7045] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Since the first report of RNA interference (RNAi) less than a decade ago, this type of molecular intervention has been introduced to repress gene expression in vitro and also for in vivo studies in mammals. Understanding the mechanisms of action of synthetic small interfering RNAs (siRNAs) underlies use as therapeutic agents in the areas of cancer and viral infection. Recent studies have also promoted different theories about cell-specific targeting of siRNAs. Design and delivery strategies for successful treatment of human diseases are becomingmore established and relationships between miRNA and RNAi pathways have been revealed as virus-host cell interactions. Although both are well conserved in plants, invertebrates and mammals, there is also variabilityand a more complete understanding of differences will be needed for optimal application. RNA interference (RNAi) is rapid, cheap and selective in complex biological systems and has created new insight sin fields of cancer research, genetic disorders, virology and drug design. Our knowledge about the role of miRNAs and siRNAs pathways in virus-host cell interactions in virus infected cells is incomplete. There are different viral diseases but few antiviral drugs are available. For example, acyclovir for herpes viruses, alpha-interferon for hepatitis C and B viruses and anti-retroviral for HIV are accessible. Also cancer is obviously an important target for siRNA-based therapies, but the main problem in cancer therapy is targeting metastatic cells which spread from the original tumor. There are also other possible reservations and problems that might delay or even hinder siRNA-based therapies for the treatment of certain conditions; however, this remains the most promising approach for a wide range of diseases. Clearly, more studies must be done to allow efficient delivery and better understanding of unwanted side effects of siRNA-based therapies. In this review miRNA and RNAi biology, experimental design, anti-viral and anti-cancer effects are discussed.
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Affiliation(s)
- Hamid Reza Mollaie
- Department of Virology, Iran University of Medical Sciences, Tehran, Iran E-mail :
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Kempf BJ, Barton DJ. Picornavirus RNA polyadenylation by 3D(pol), the viral RNA-dependent RNA polymerase. Virus Res 2015; 206:3-11. [PMID: 25559071 PMCID: PMC4801031 DOI: 10.1016/j.virusres.2014.12.030] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2014] [Revised: 12/15/2014] [Accepted: 12/24/2014] [Indexed: 11/06/2022]
Abstract
Picornaviral RdRPs are responsible for the polyadenylation of viral RNA. Reiterative transcription mechanisms occur during replication of poly(A) tails. Conserved RdRP structures influence the size of poly(A) tails. Common features of picornavirus RdRPs and telomerase reverse transcriptase. Poly(A) tails are a telomere of picornavirus RNA genomes.
Poly(A) tails are functionally important features of all picornavirus RNA genomes. Some viruses have genomes with relatively short poly(A) tails (encephalomyocarditis virus) whereas others have genomes with longer poly(A) tails (polioviruses and rhinoviruses). Here we review the polyadenylation of picornavirus RNA as it relates to the structure and function of 3Dpol. Poliovirus 3Dpol uses template-dependent reiterative transcription mechanisms as it replicates the poly(A) tails of viral RNA (Steil et al., 2010). These mechanisms are analogous to those involved in the polyadenylation of vesicular stomatitis virus and influenza virus mRNAs. 3Dpol residues intimately associated with viral RNA templates and products regulate the size of poly(A) tails in viral RNA (Kempf et al., 2013). Consistent with their ancient evolutionary origins, picornavirus 3Dpol and telomerase reverse transcriptase (TERT) share structural and functional features. Structurally, both 3Dpol and TERT assume a “right-hand” conformation with thumb, palm and fingers domains encircling templates and products. Functionally, both 3Dpol and TERT use template-dependent reiterative transcription mechanisms to synthesize repetitive sequences: poly(A) tails in the case of picornavirus RNA genomes and DNA telomeres in the case of eukaryotic chromosomes. Thus, picornaviruses and their eukaryotic hosts (humans and animals) maintain the 3′ ends of their respective genomes via evolutionarily related mechanisms.
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Affiliation(s)
- Brian J Kempf
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO 80045, United States
| | - David J Barton
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO 80045, United States.
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22
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Forrest S, Lear Z, Herod MR, Ryan M, Rowlands DJ, Stonehouse NJ. Inhibition of the foot-and-mouth disease virus subgenomic replicon by RNA aptamers. J Gen Virol 2014; 95:2649-2657. [PMID: 25096816 PMCID: PMC4233629 DOI: 10.1099/vir.0.067751-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Accepted: 08/01/2014] [Indexed: 12/23/2022] Open
Abstract
We have previously documented the inhibitory activity of RNA aptamers to the RNA-dependent RNA polymerase of foot-and-mouth disease virus (3D(pol)). Here we report their modification and use with a subgenomic replicon incorporating GFP (pGFP-PAC replicon), allowing replication to be monitored and quantified in real-time. GFP expression in transfected BHK-21 cells reached a maximum at approximately 8 h post-transfection, at which time change in morphology of the cells was consistent with a virus-induced cytopathic effect. However, transfection of replicon-bearing cells with a 3D(pol) aptamer RNA resulted in inhibition of GFP expression and maintenance of normal cell morphology, whereas a control aptamer RNA had little effect. The inhibition was correlated with a reduction in 3D(pol) (detected by immunoblotting) and shown to be dose dependent. The 3D(pol) aptamers appeared to be more effective than 2'-C-methylcytidine (2'CMC). Aptamers to components of the replication complex are therefore useful molecular tools for studying viral replication and also have potential as diagnostic molecules in the future.
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Affiliation(s)
- Sophie Forrest
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
| | - Zoe Lear
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
| | - Morgan R. Herod
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
| | - Martin Ryan
- Biomedical Sciences Research Complex (BSRC), School of Biology, University of St Andrews, North Haugh, St Andrews, Fife KY16 9ST, UK
| | - David J. Rowlands
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
| | - Nicola J. Stonehouse
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
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23
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Han SC, Guo HC, Sun SQ. Three-dimensional structure of foot-and-mouth disease virus and its biological functions. Arch Virol 2014; 160:1-16. [PMID: 25377637 DOI: 10.1007/s00705-014-2278-x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2014] [Accepted: 10/31/2014] [Indexed: 11/26/2022]
Abstract
Foot-and-mouth disease (FMD), an acute, violent, infectious disease of cloven-hoofed animals, remains widespread in most parts of the world. It can lead to a major plague of livestock and an economical catastrophe. Structural studies of FMD virus (FMDV) have greatly contributed to our understanding of the virus life cycle and provided new horizons for the control and eradication of FMDV. To examine host-FMDV interactions and viral pathogenesis from a structural perspective, the structures of viral structural and non-structural proteins are reviewed in the context of their relevance for virus assembly and dissociation, formation of capsid-like particles and virus-receptor complexes, and viral penetration and uncoating. Moreover, possibilities for devising novel antiviral treatments are discussed.
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Affiliation(s)
- Shi-Chong Han
- State Key Laboratory of Veterinary Etiological Biology and OIE/National Foot and Mouth Disease Reference Laboratory, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, 730046, Gansu, People's Republic of China
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24
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Verdaguer N, Ferrero D, Murthy MRN. Viruses and viral proteins. IUCRJ 2014; 1:492-504. [PMID: 25485129 PMCID: PMC4224467 DOI: 10.1107/s205225251402003x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Accepted: 09/04/2014] [Indexed: 05/30/2023]
Abstract
For more than 30 years X-ray crystallography has been by far the most powerful approach for determining the structures of viruses and viral proteins at atomic resolution. The information provided by these structures, which covers many important aspects of the viral life cycle such as cell-receptor recognition, viral entry, nucleic acid transfer and genome replication, has extensively enriched our vision of the virus world. Many of the structures available correspond to potential targets for antiviral drugs against important human pathogens. This article provides an overview of the current knowledge of different structural aspects of the above-mentioned processes.
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Affiliation(s)
- Nuria Verdaguer
- Institut de Biología Molecular de Barcelona, CSIC, Parc Científic de Barcelona, Baldiri i Reixac 15, 08028-Barcelona, Spain
| | - Diego Ferrero
- Institut de Biología Molecular de Barcelona, CSIC, Parc Científic de Barcelona, Baldiri i Reixac 15, 08028-Barcelona, Spain
| | - Mathur R. N. Murthy
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012, India
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25
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Boehr DD, Liu X, Yang X. Targeting structural dynamics of the RNA-dependent RNA polymerase for anti-viral strategies. Curr Opin Virol 2014; 9:194-200. [PMID: 25224392 DOI: 10.1016/j.coviro.2014.08.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Accepted: 08/28/2014] [Indexed: 10/24/2022]
Abstract
The RNA-dependent RNA polymerase is responsible for genome replication of RNA viruses. Nuclear magnetic resonance experiments and molecular dynamics simulations have indicated that efficient and faithful polymerase function requires highly coordinated internal protein motions. Interference with these motions, either through amino acid substitutions or small molecule binding, can disrupt polymerase and virus function. In particular, these studies have pointed toward highly conserved structural elements, like the motif-D active-site loop, that can be modified to generate polymerases with desired properties. Viruses encoding engineered polymerases might serve as live, attenuated vaccine strains. Further elucidation of polymerase structural dynamics will also provide new avenues for anti-viral drug design.
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Affiliation(s)
- David D Boehr
- Department of Chemistry, The Pennsylvania State University, University Park, PA 16802, USA.
| | - Xinran Liu
- Department of Chemistry, The Pennsylvania State University, University Park, PA 16802, USA
| | - Xiaorong Yang
- Department of Chemistry, The Pennsylvania State University, University Park, PA 16802, USA
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26
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Holien JK, Gazina EV, Elliott RW, Jarrott B, Cameron CE, Williams SJ, Parker MW, Petrou S. Computational Analysis of Amiloride Analogue Inhibitors of Coxsackievirus B3 RNA Polymerase. ACTA ACUST UNITED AC 2014; Suppl 9:004. [PMID: 26491236 DOI: 10.4172/jpb.s9-004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Coxsackievirus B3 (CVB3) is a picornavirus that is responsible for a significant proportion of human myocarditis. However, no antiviral treatment is currently available to treat this disease or indeed any picornaviral infections. Previously it was shown that amiloride and its derivative 5-(N-ethyl-N-isopropyl)amiloride inhibit the in vitro enzymatic activity of CVB3 RNA polymerase (3Dpol). Here we measure and compare the inhibitory activity of ten amiloride analogues against CVB3 3Dpol. We show that replacement of the 3,5-diaminopyrazinyl moiety of amiloride causes loss of the inhibitory activity, whereas modifications at the 5-amino and guanidino groups increase or decrease potency. Importantly, a combination of substitutions at both the 5-amino and guanidino groups produced a compound that was more potent than its singly modified precursors. The compounds were computationally-docked into available crystal structures of CVB3 3Dpol in order to obtain a structural explanation for the activities of the analogues. To create a robust model which explained the biological activity, optimization of one of the CVB3 3Dpol crystal structures to take into account active site flexibility was necessary, together with the use of consensus docking from two different docking algorithms. This robust predictive 3D atomic model provides insights into the interactions required for inhibitor binding and provides a promising basis for the development of more potent inhibitors against this important therapeutic target.
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Affiliation(s)
- Jessica K Holien
- Structural Biology Laboratory and ACRF Rational Drug Discovery Centre, St. Vincent's Institute of Medical Research, 9 Princes St, Fitzroy, Victoria 3065, Australia
| | - Elena V Gazina
- Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Victoria 3010, Australia
| | - Robert W Elliott
- School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Bevyn Jarrott
- Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Victoria 3010, Australia
| | - Craig E Cameron
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA
| | - Spencer J Williams
- School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Michael W Parker
- Structural Biology Laboratory and ACRF Rational Drug Discovery Centre, St. Vincent's Institute of Medical Research, 9 Princes St, Fitzroy, Victoria 3065, Australia.,Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Steven Petrou
- Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Victoria 3010, Australia.,Department of Electrical and Electronic Engineering, The University of Melbourne.,Centre for Neural Engineering, The University of Melbourne, Victoria 3010, Australia
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27
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López-Jiménez AJ, Clemente-Casares P, Sabariegos R, Llanos-Valero M, Bellón-Echeverría I, Encinar JA, Kaushik-Basu N, Froeyen M, Mas A. Hepatitis C virus polymerase-polymerase contact interface: significance for virus replication and antiviral design. Antiviral Res 2014; 108:14-24. [PMID: 24815023 DOI: 10.1016/j.antiviral.2014.04.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Revised: 04/13/2014] [Accepted: 04/21/2014] [Indexed: 11/25/2022]
Abstract
The hepatitis C virus (HCV) replicates its genome in replication complexes located in micro-vesicles derived from endoplasmic reticulum. The composition of these replication complexes indicates that proteins, both viral and cellular in origin, are at high concentrations. Under these conditions, protein-protein interactions must occur although their role in the replication pathways is unknown. HCV RNA-dependent RNA-polymerase (NS5B) initiates RNA synthesis in these vesicles by a de novo (DN) mechanism. After initiation, newly synthesized dsRNA could induce conformational changes that direct the transition from an initiating complex into a processive elongation complex. In this report, we analyze the role played by NS5B-NS5B intermolecular interactions controlling these conformational rearrangements. Based on NS5B protein-protein docking and molecular dynamics simulations, we constructed mutants of residues predicted to be involved in protein-protein interactions. Changes at these positions induced severe defects in both the activity of the enzyme and the replication of a subgenomic replicon. Thus, mutations at the interaction surface decreased both DN synthesis initiation and processive elongation activities. Based on this analysis, we define at an atomic level an NS5B homomeric interaction model that connects the T-helix in the thumb subdomain of one monomer, with the F-helix of the fingers subdomain in other monomer. Knowing the molecular determinants involved in viral replication could be helpful to delineate new and powerful antiviral strategies.
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Affiliation(s)
- Alberto José López-Jiménez
- Centro Regional de Investigaciones Biomédicas (CRIB), Universidad de Castilla-La Mancha, Albacete 02008, Spain
| | - Pilar Clemente-Casares
- Centro Regional de Investigaciones Biomédicas (CRIB), Universidad de Castilla-La Mancha, Albacete 02008, Spain; School of Pharmacy, Universidad de Castilla-La Mancha, Albacete 02008, Spain; Viral Hepatitis Study Group, Spanish Society of Virology, Madrid, Spain
| | - Rosario Sabariegos
- Centro Regional de Investigaciones Biomédicas (CRIB), Universidad de Castilla-La Mancha, Albacete 02008, Spain; School of Medicine, Universidad de Castilla-La Mancha, Albacete 02008, Spain; Viral Hepatitis Study Group, Spanish Society of Virology, Madrid, Spain
| | - María Llanos-Valero
- Centro Regional de Investigaciones Biomédicas (CRIB), Universidad de Castilla-La Mancha, Albacete 02008, Spain
| | - Itxaso Bellón-Echeverría
- Centro Regional de Investigaciones Biomédicas (CRIB), Universidad de Castilla-La Mancha, Albacete 02008, Spain
| | - José Antonio Encinar
- Instituto de Biología Molecular y Celular, Universidad Miguel Hernández, Elche 03202, Spain
| | - Neerja Kaushik-Basu
- Department of Biochemistry and Molecular Biology, Rutgers, The State University of New Jersey, New Jersey Medical School, 185 South Orange Avenue, Newark, NJ 07103, United States
| | - Mathy Froeyen
- Laboratory for Medicinal Chemistry, Rega Institute for Medical Research, K.U. Leuven, Belgium
| | - Antonio Mas
- Centro Regional de Investigaciones Biomédicas (CRIB), Universidad de Castilla-La Mancha, Albacete 02008, Spain; School of Pharmacy, Universidad de Castilla-La Mancha, Albacete 02008, Spain; Viral Hepatitis Study Group, Spanish Society of Virology, Madrid, Spain; Unidad de Biomedicina, CSIC-UCLM, Spain.
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28
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Caillet-Saguy C, Lim SP, Shi PY, Lescar J, Bressanelli S. Polymerases of hepatitis C viruses and flaviviruses: Structural and mechanistic insights and drug development. Antiviral Res 2014; 105:8-16. [DOI: 10.1016/j.antiviral.2014.02.006] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 01/31/2014] [Accepted: 02/10/2014] [Indexed: 11/29/2022]
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29
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Antal CE, Violin JD, Kunkel MT, Skovsø S, Newton AC. Intramolecular conformational changes optimize protein kinase C signaling. ACTA ACUST UNITED AC 2014; 21:459-469. [PMID: 24631122 DOI: 10.1016/j.chembiol.2014.02.008] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2013] [Revised: 01/31/2014] [Accepted: 02/02/2014] [Indexed: 11/25/2022]
Abstract
Optimal tuning of enzyme signaling is critical for cellular homeostasis. We use fluorescence resonance energy transfer reporters in live cells to follow conformational transitions that tune the affinity of a multidomain signal transducer, protein kinase C (PKC), for optimal response to second messengers. This enzyme comprises two diacylglycerol sensors, the C1A and C1B domains, that have a sufficiently high intrinsic affinity for ligand so that the enzyme would be in a ligand-engaged, active state if not for mechanisms that mask its domains. We show that both diacylglycerol sensors are exposed in newly synthesized PKC and that conformational transitions following priming phosphorylations mask the domains so that the lower affinity sensor, the C1B domain, is the primary diacylglycerol binder. The conformational rearrangements of PKC serve as a paradigm for how multimodule transducers optimize their dynamic range of signaling.
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Affiliation(s)
- Corina E Antal
- Department of Pharmacology, University of California at San Diego, La Jolla, CA 92093, USA; Biomedical Sciences Graduate Program, University of California at San Diego, La Jolla, CA 92093, USA
| | - Jonathan D Violin
- Department of Pharmacology, University of California at San Diego, La Jolla, CA 92093, USA; Biomedical Sciences Graduate Program, University of California at San Diego, La Jolla, CA 92093, USA
| | - Maya T Kunkel
- Department of Pharmacology, University of California at San Diego, La Jolla, CA 92093, USA
| | - Søs Skovsø
- Department of Pharmacology, University of California at San Diego, La Jolla, CA 92093, USA; Institute for Cellular and Molecular Medicine, Panum Institute, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen, Denmark
| | - Alexandra C Newton
- Department of Pharmacology, University of California at San Diego, La Jolla, CA 92093, USA.
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30
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The crystal structure of a cardiovirus RNA-dependent RNA polymerase reveals an unusual conformation of the polymerase active site. J Virol 2014; 88:5595-607. [PMID: 24600002 DOI: 10.1128/jvi.03502-13] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
UNLABELLED Encephalomyocarditis virus (EMCV) is a member of the Cardiovirus genus within the large Picornaviridae family, which includes a number of important human and animal pathogens. The RNA-dependent RNA polymerase (RdRp) 3Dpol is a key enzyme for viral genome replication. In this study, we report the X-ray structures of two different crystal forms of the EMCV RdRp determined at 2.8- and 2.15-Å resolution. The in vitro elongation and VPg uridylylation activities of the purified enzyme have also been demonstrated. Although the overall structure of EMCV 3Dpol is shown to be similar to that of the known RdRps of other members of the Picornaviridae family, structural comparisons show a large reorganization of the active-site cavity in one of the crystal forms. The rearrangement affects mainly motif A, where the conserved residue Asp240, involved in ribonucleoside triphosphate (rNTP) selection, and its neighbor residue, Phe239, move about 10 Å from their expected positions within the ribose binding pocket toward the entrance of the rNTP tunnel. This altered conformation of motif A is stabilized by a cation-π interaction established between the aromatic ring of Phe239 and the side chain of Lys56 within the finger domain. Other contacts, involving Phe239 and different residues of motif F, are also observed. The movement of motif A is connected with important conformational changes in the finger region flanked by residues 54 to 63, harboring Lys56, and in the polymerase N terminus. The structures determined in this work provide essential information for studies on the cardiovirus RNA replication process and may have important implications for the development of new antivirals targeting the altered conformation of motif A. IMPORTANCE The Picornaviridae family is one of the largest virus families known, including many important human and animal pathogens. The RNA-dependent RNA polymerase (RdRp) 3Dpol is a key enzyme for picornavirus genome replication and a validated target for the development of antiviral therapies. Solving the X-ray structure of the first cardiovirus RdRp, EMCV 3Dpol, we captured an altered conformation of a conserved motif in the polymerase active site (motif A) containing the aspartic acid residue involved in rNTP selection and binding. This altered conformation of motif A, which interferes with the correct positioning of the rNTP substrate in the active site, is stabilized by a number of residues strictly conserved among picornaviruses. The rearrangements observed suggest that this motif A segment is a dynamic element that can be modulated by external effectors, either activating or inhibiting enzyme activity, and this type of modulation appears to be general to all picornaviruses.
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Establishment and evaluation of stable cell lines inhibiting foot-and-mouth disease virus by RNA interference. BIOMED RESEARCH INTERNATIONAL 2014; 2014:109428. [PMID: 24683539 PMCID: PMC3934452 DOI: 10.1155/2014/109428] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/01/2013] [Accepted: 01/01/2014] [Indexed: 11/18/2022]
Abstract
RNA interference (RNAi) has been proved to be a powerful tool for foot-and-mouth disease virus FMDV inhibition in vitro and in vivo. We established five stable baby hamster kidney 21 cell lines (BHK-21) containing five short hairpin RNAs (shRNAs) expression plasmids (p3D1shRNA, p3D2shRNA, p3D3shRNA, p3D4shRNA, and p3D5shRNA) targeting 3D gene of FMDV. Immunofluorescent assay, virus titration, and real-time quantitative reverse transcription polymerase chain reaction (Q-RT-PCR) were conducted to detect the effect of shRNAs on FMDV replication. After challenged with FMDV of O/CHA/99, two cell lines (p3D1shRNA and p3D4shRNA) showed a significant reduction in the synthesis of viral protein and RNA, accompanied by a sharp decrease in viral yield, and the inhibition could last for at least thirty passages. We developed an efficient procedure for the establishment and evaluation of stable cell lines for anti-FMDV research based on RNAi technology, which can be a candidate method for anti-FMDV research.
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Affiliation(s)
- David D Boehr
- Department of Chemistry, The Pennsylvania State University, University Park, PA 16802, USA.
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33
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Ma XX, Feng YP, Liu JL, Ma B, Chen L, Zhao YQ, Guo PH, Guo JZ, Ma ZR, Zhang J. The effects of the codon usage and translation speed on protein folding of 3Dpol of foot-and-mouth disease virus. Vet Res Commun 2013; 37:243-50. [DOI: 10.1007/s11259-013-9564-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/10/2013] [Indexed: 10/26/2022]
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34
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McDonald SM. RNA synthetic mechanisms employed by diverse families of RNA viruses. WILEY INTERDISCIPLINARY REVIEWS-RNA 2013; 4:351-67. [PMID: 23606593 PMCID: PMC7169773 DOI: 10.1002/wrna.1164] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
RNA viruses are ubiquitous in nature, infecting every known organism on the planet. These viruses can also be notorious human pathogens with significant medical and economic burdens. Central to the lifecycle of an RNA virus is the synthesis of new RNA molecules, a process that is mediated by specialized virally encoded enzymes called RNA‐dependent RNA polymerases (RdRps). RdRps directly catalyze phosphodiester bond formation between nucleoside triphosphates in an RNA‐templated manner. These enzymes are strikingly conserved in their structural and functional features, even among diverse RNA viruses belonging to different families. During host cell infection, the activities of viral RdRps are often regulated by viral cofactor proteins. Cofactors can modulate the type and timing of RNA synthesis by directly engaging the RdRp and/or by indirectly affecting its capacity to recognize template RNA. High‐resolution structures of RdRps as apoenzymes, bound to RNA templates, in the midst of catalysis, and/or interacting with regulatory cofactor proteins, have dramatically increased our understanding of viral RNA synthetic mechanisms. Combined with elegant biochemical studies, such structures are providing a scientific platform for the rational design of antiviral agents aimed at preventing and treating RNA virus‐induced diseases. WIREs RNA 2013, 4:351–367. doi: 10.1002/wrna.1164 This article is categorized under:
RNA Interactions with Proteins and Other Molecules > RNA–Protein Complexes RNA in Disease and Development > RNA in Disease
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Affiliation(s)
- Sarah M McDonald
- Virginia Tech Carilion Research Institute and School of Medicine, Roanoke, VA, USA.
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Garriga D, Ferrer-Orta C, Querol-Audí J, Oliva B, Verdaguer N. Role of motif B loop in allosteric regulation of RNA-dependent RNA polymerization activity. J Mol Biol 2013; 425:2279-87. [PMID: 23542342 DOI: 10.1016/j.jmb.2013.03.034] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2013] [Revised: 03/15/2013] [Accepted: 03/21/2013] [Indexed: 01/22/2023]
Abstract
Increasing amounts of data show that conformational dynamics are essential for protein function. Unveiling the mechanisms by which this flexibility affects the activity of a given enzyme and how it is controlled by other effectors opens the door to the design of a new generation of highly specific drugs. Viral RNA-dependent RNA polymerases (RdRPs) are not an exception. These enzymes, essential for the multiplication of all RNA viruses, catalyze the formation of phosphodiester bonds between ribonucleotides in an RNA-template-dependent fashion. Inhibition of RdRP activity will prevent genome replication and virus multiplication. Thus, RdRPs, like the reverse transcriptase of retroviruses, are validated targets for the development of antiviral therapeutics. X-ray crystallography of RdRPs trapped in multiple steps throughout the catalytic process, together with NMR data and molecular dynamics simulations, have shown that all polymerase regions contributing to conserved motifs required for substrate binding, catalysis and product release are highly flexible and some of them are predicted to display correlated motions. All these dynamic elements can be modulated by external effectors, which appear as useful tools for the development of effective allosteric inhibitors that block or disturb the flexibility of these enzymes, ultimately impeding their function. Among all movements observed, motif B, and the B-loop at its N-terminus in particular, appears as a new potential druggable site.
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Affiliation(s)
- Damià Garriga
- Institut de Biología Molecular de Barcelona (CSIC), Parc Científic de Barcelona, Baldiri i Reixac 10-12, 08028 Barcelona, Spain
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Ribavirin-resistant mutants of human enterovirus 71 express a high replication fidelity phenotype during growth in cell culture. J Virol 2012; 87:1759-69. [PMID: 23175376 DOI: 10.1128/jvi.02139-12] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
It has been shown in animal models that ribavirin-resistant poliovirus with a G64S mutation in its 3D polymerase has high replication fidelity coupled with attenuated virulence. Here, we describe the effects of mutagenesis in the human enterovirus 71 (HEV71) 3D polymerase on ribavirin resistance and replication fidelity. Seven substitutions were introduced at amino acid position 3D-G64 of a HEV71 full-length infectious cDNA clone (26M). Viable clone-derived virus populations were rescued from the G64N, G64R, and G64T mutant cDNA clones. The clone-derived G64R and G64T mutant virus populations were resistant to growth inhibition in the presence of 1,600 μM ribavirin, whereas the growth of parental 26M and the G64N mutant viruses were inhibited in the presence of 800 μM ribavirin. Nucleotide sequencing of the 2C and 3D coding regions revealed that the rate of random mutagenesis after 13 passages in the presence of 400 μM ribavirin was nearly 10 times higher in the 26M genome than in the mutant G64R virus genome. Furthermore, random mutations acquired in the 2C coding regions of 26M and G64N conferred resistance to growth inhibition in the presence of 0.5 mM guanidine, whereas the G64R and G64T mutant virus populations remained susceptible to growth inhibition by 0.5 mM guanidine. Interestingly, a S264L mutation identified in the 3D coding region of 26M after ribavirin selection was also associated with both ribavirin-resistant and high replication fidelity phenotypes. These findings are consistent with the hypothesis that the 3D-G64R, 3D-G64T, and 3D-S264L mutations confer resistance upon HEV71 to the antiviral mutagen ribavirin, coupled with a high replication fidelity phenotype during growth in cell culture.
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Esmaelizad M, Jelokhani-Niaraki S, Hashemnejad K, Kamalzadeh M, Lotfi M. Molecular characterization of amino acid deletion in VP1 (1D) protein and novel amino acid substitutions in 3D polymerase protein of foot and mouth disease virus subtype A/Iran87. J Vet Sci 2012; 12:363-71. [PMID: 22122902 PMCID: PMC3232396 DOI: 10.4142/jvs.2011.12.4.363] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The nucleotide sequence of the VP1 (1D) and partial 3D polymerase (3Dpol) coding regions of the foot and mouth disease virus (FMDV) vaccine strain A/Iran87, a highly passaged isolate (~150 passages), was determined and aligned with previously published FMDV serotype A sequences. Overall analysis of the amino acid substitutions revealed that the partial 3Dpol coding region contained four amino acid alterations. Amino acid sequence comparison of the VP1 coding region of the field isolates revealed deletions in the highly passaged Iranian isolate (A/Iran87). The prominent G-H loop of the FMDV VP1 protein contains the conserved arginine-glycine-aspartic acid (RGD) tripeptide, which is a well-known ligand for a specific cell surface integrin. Despite losing the RGD sequence of the VP1 protein and an Asp26→Glu substitution in a beta sheet located within a small groove of the 3Dpol protein, the virus grew in BHK 21 suspension cell cultures. Since this strain has been used as a vaccine strain, it may be inferred that the RGD deletion has no critical role in virus attachment to the cell during the initiation of infection. It is probable that this FMDV subtype can utilize other pathways for cell attachment.
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Affiliation(s)
- Majid Esmaelizad
- Department of Biotechnology, Razi Vaccine and Serum Research Institute, Karaj 3197619751, Iran.
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Abstract
Evolution of RNA viruses occurs through disequilibria of collections of closely related mutant spectra or mutant clouds termed viral quasispecies. Here we review the origin of the quasispecies concept and some biological implications of quasispecies dynamics. Two main aspects are addressed: (i) mutant clouds as reservoirs of phenotypic variants for virus adaptability and (ii) the internal interactions that are established within mutant spectra that render a virus ensemble the unit of selection. The understanding of viruses as quasispecies has led to new antiviral designs, such as lethal mutagenesis, whose aim is to drive viruses toward low fitness values with limited chances of fitness recovery. The impact of quasispecies for three salient human pathogens, human immunodeficiency virus and the hepatitis B and C viruses, is reviewed, with emphasis on antiviral treatment strategies. Finally, extensions of quasispecies to nonviral systems are briefly mentioned to emphasize the broad applicability of quasispecies theory.
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Affiliation(s)
- Esteban Domingo
- Centro de Biología Molecular Severo Ochoa (CSIC-UAM), C/ Nicolás Cabrera, Universidad Autónoma de Madrid, Cantoblanco, Madrid, Spain.
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Viral targets of acylguanidines. Drug Discov Today 2012; 17:1039-43. [PMID: 22580299 PMCID: PMC7108427 DOI: 10.1016/j.drudis.2012.05.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2011] [Revised: 03/12/2012] [Accepted: 05/02/2012] [Indexed: 01/01/2023]
Abstract
Acylguanidines are a new class of antiviral compounds with the unique ability to target both RNA polymerase and transmembrane proteins of viruses from different families. Importantly, they inhibit proteins which are not targeted by existing antiviral therapies, for example, Vpu of HIV type 1, p7 of hepatitis C virus, E of severe acute respiratory syndrome coronavirus and RNA-dependent RNA polymerase of coxsackievirus B3. BIT225, developed by Biotron Limited, is the first acylguanidine in clinical trials against HIV type 1 and hepatitis C virus. In this article we focus on the mechanisms of inhibition of viral proteins by acylguanidines.
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Kortus MG, Kempf BJ, Haworth KG, Barton DJ, Peersen OB. A template RNA entry channel in the fingers domain of the poliovirus polymerase. J Mol Biol 2012; 417:263-78. [PMID: 22321798 PMCID: PMC3325025 DOI: 10.1016/j.jmb.2012.01.049] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2011] [Revised: 01/24/2012] [Accepted: 01/26/2012] [Indexed: 01/10/2023]
Abstract
Positive-strand RNA viruses within the Picornaviridae family express an RNA-dependent RNA polymerase, 3D(pol), that is required for viral RNA replication. Structures of 3D(pol) from poliovirus, coxsackievirus, human rhinoviruses, and other picornaviruses reveal a putative template RNA entry channel on the surface of the enzyme fingers domain. Basic amino acids and tyrosine residues along this entry channel are predicted to form ionic and base stacking interactions with the viral RNA template as it enters the polymerase active site. We generated a series of alanine substitution mutations at these residues in the poliovirus polymerase and assayed their effects on template RNA binding, RNA synthesis initiation, rates of RNA elongation, elongation complex (EC) stability, and virus growth. The results show that basic residues K125, R128, and R188 are important for template RNA binding, while tyrosines Y118 and Y148 are required for efficient initiation of RNA synthesis and for EC stability. Alanine substitutions of tyrosines 118 and 148 at the tip of the 3D(pol) pinky finger drastically decreased the rate of initiation as well as EC stability, but without affecting template RNA binding or RNA elongation rates. Viable poliovirus was recovered from HeLa cells transfected with mutant RNAs; however, mutations that dramatically inhibited template RNA binding (K125A-K126A and R188A), RNA synthesis initiation (Y118A, Y148A), or EC stability (Y118A, Y148A) were not stably maintained in progeny virus. These data identify key residues within the template RNA entry channel and begin to define their distinct mechanistic roles within RNA ECs.
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Affiliation(s)
- Matthew G. Kortus
- Department of Biochemistry & Molecular Biology, Colorado State University, 1870 Campus Delivery, Colorado State University, Fort Collins, CO80523-1870
| | - Brian J. Kempf
- Department of Microbiology, University of Colorado School of Medicine, Anschutz Medical Campus, Building RC-1 North, Room 9116, 12800 East 19th Avenue, MS8333, Aurora, CO 80045
| | - Kevin G. Haworth
- Department of Biochemistry & Molecular Biology, Colorado State University, 1870 Campus Delivery, Colorado State University, Fort Collins, CO80523-1870
| | - David J. Barton
- Department of Microbiology, University of Colorado School of Medicine, Anschutz Medical Campus, Building RC-1 North, Room 9116, 12800 East 19th Avenue, MS8333, Aurora, CO 80045
| | - Olve B. Peersen
- Department of Biochemistry & Molecular Biology, Colorado State University, 1870 Campus Delivery, Colorado State University, Fort Collins, CO80523-1870
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Dochow M, Krumm SA, Crowe JE, Moore ML, Plemper RK. Independent structural domains in paramyxovirus polymerase protein. J Biol Chem 2012; 287:6878-91. [PMID: 22215662 DOI: 10.1074/jbc.m111.325258] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
All enzymatic activities required for genomic replication and transcription of nonsegmented negative strand RNA viruses (or Mononegavirales) are believed to be concentrated in the viral polymerase (L) protein. However, our insight into the organization of these different enzymatic activities into a bioactive tertiary structure remains rudimentary. Fragments of Mononegavirales polymerases analyzed to date cannot restore bioactivity through trans-complementation, unlike the related L proteins of segmented NSVs. We investigated the domain organization of phylogenetically diverse Paramyxovirus L proteins derived from measles virus (MeV), Nipah virus (NiV), and respiratory syncytial virus (RSV). Through a comprehensive in silico and experimental analysis of domain intersections, we defined MeV L position 615 as an interdomain candidate in addition to the previously reported residue 1708. Only position 1708 of MeV and the homologous positions in NiV and RSV L also tolerated the insertion of epitope tags. Splitting of MeV L at residue 1708 created fragments that were unable to physically interact and trans-complement, but strikingly, these activities were reconstituted by the addition of dimerization tags to the fragments. Equivalently split fragments of NiV, RSV, and MeV L oligomerized with comparable efficiency in all homo- and heterotypic combinations, but only the homotypic pairs were able to trans-complement. These results demonstrate that synthesis as a single polypeptide is not required for the Mononegavirales polymerases to adopt a proper tertiary conformation. Paramyxovirus polymerases are composed of at least two truly independent folding domains that lack a traditional interface but require molecular compatibility for bioactivity. The functional probing of the L domain architecture through trans-complementation is anticipated to be applicable to all Mononegavirales polymerases.
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Affiliation(s)
- Melanie Dochow
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia 30322, USA
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42
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Matsuo E, Roy P. Bluetongue virus VP1 polymerase activity in vitro: template dependency, dinucleotide priming and cap dependency. PLoS One 2011; 6:e27702. [PMID: 22110731 PMCID: PMC3216989 DOI: 10.1371/journal.pone.0027702] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2011] [Accepted: 10/22/2011] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Bluetongue virus (BTV) protein, VP1, is known to possess an intrinsic polymerase function, unlike rotavirus VP1, which requires the capsid protein VP2 for its catalytic activity. However, compared with the polymerases of other members of the Reoviridae family, BTV VP1 has not been characterized in detail. METHODS AND FINDINGS Using an in vitro polymerase assay system, we demonstrated that BTV VP1 could synthesize the ten dsRNAs simultaneously from BTV core-derived ssRNA templates in a single in vitro reaction as well as genomic dsRNA segments from rotavirus core-derived ssRNA templates that possess no sequence similarity with BTV. In contrast, dsRNAs were not synthesized from non-viral ssRNA templates by VP1, unless they were fused with specific BTV sequences. Further, we showed that synthesis of dsRNAs from capped ssRNA templates was significantly higher than that from uncapped ssRNA templates and the addition of dinucleotides enhanced activity as long as the last base of the dinucleotide complemented the 3' -terminal nucleotide of the ssRNA template. CONCLUSIONS We showed that the polymerase activity was stimulated by two different factors: cap structure, likely due to allosteric effect, and dinucleotides due to priming. Our results also suggested the possible presence of cis-acting elements shared by ssRNAs in the members of family Reoviridae.
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Affiliation(s)
- Eiko Matsuo
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Polly Roy
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
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Perales C, Martín V, Domingo E. Lethal mutagenesis of viruses. Curr Opin Virol 2011; 1:419-22. [PMID: 22440845 DOI: 10.1016/j.coviro.2011.09.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2011] [Accepted: 09/05/2011] [Indexed: 02/09/2023]
Abstract
Lethal mutagenesis aims at extinguishing viruses by increased mutagenesis prompted by virus-specific mutagenic agents, mainly nucleoside analogues. It is derived from the error threshold relationship of quasispecies theory, and it is slowly finding its way towards a clinical application. We summarize the current situation of research in this field of antiviral therapy.
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Affiliation(s)
- Celia Perales
- Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Consejo Superior de Investigaciones Científicas, Campus de Cantoblanco, 28049, Madrid, Spain
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Noton SL, Fearns R. The first two nucleotides of the respiratory syncytial virus antigenome RNA replication product can be selected independently of the promoter terminus. RNA (NEW YORK, N.Y.) 2011; 17:1895-1906. [PMID: 21878549 PMCID: PMC3185921 DOI: 10.1261/rna.2813411] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2011] [Accepted: 07/31/2011] [Indexed: 05/31/2023]
Abstract
There is limited knowledge regarding how the RNA-dependent RNA polymerases of the nonsegmented negative-strand RNA viruses initiate genome replication. In a previous study of respiratory syncytial virus (RSV) RNA replication, we found evidence that the polymerase could select the 5'-ATP residue of the genome RNA independently of the 3' nucleotide of the template. To investigate if a similar mechanism is used during antigenome synthesis, a study of initiation from the RSV leader (Le) promoter was performed using an intracellular minigenome assay in which RNA replication was restricted to a single step, so that the products examined were derived only from input mutant templates. Templates in which Le nucleotides 1U, or 1U and 2G, were deleted directed efficient replication, and in both cases, the replication products were initiated at the wild-type position, at position -1 or -2 relative to the template, respectively. Sequence analysis of the RNA products showed that they contained ATP and CTP at the -1 and -2 positions, respectively, thus restoring the mini-antigenome RNA to wild-type sequence. These data indicate that the RSV polymerase is able to select the first two nucleotides of the antigenome and initiate at the correct position, even if the 3'-terminal two nucleotides of the template are missing. Substitution of positions +1 and +2 of the template reduced RNA replication and resulted in increased initiation at positions +3 and +5. Together these data suggest a model for how the RSV polymerase initiates antigenome synthesis.
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Affiliation(s)
- Sarah L. Noton
- Department of Microbiology, Boston University School of Medicine, Boston, Massachusetts 02118, USA
| | - Rachel Fearns
- Department of Microbiology, Boston University School of Medicine, Boston, Massachusetts 02118, USA
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Abstract
Amiloride and its derivative 5-(N-ethyl-N-isopropyl)amiloride (EIPA) were previously shown to inhibit coxsackievirus B3 (CVB3) RNA replication in cell culture, with two amino acid substitutions in the viral RNA-dependent RNA polymerase 3D(pol) conferring partial resistance of CVB3 to these compounds (D. N. Harrison, E. V. Gazina, D. F. Purcell, D. A. Anderson, and S. Petrou, J. Virol. 82:1465-1473, 2008). Here we demonstrate that amiloride and EIPA inhibit the enzymatic activity of CVB3 3D(pol) in vitro, affecting both VPg uridylylation and RNA elongation. Examination of the mechanism of inhibition of 3D(pol) by amiloride showed that the compound acts as a competitive inhibitor, competing with incoming nucleoside triphosphates (NTPs) and Mg(2+). Docking analysis suggested a binding site for amiloride and EIPA in 3D(pol), located in close proximity to one of the Mg(2+) ions and overlapping the nucleotide binding site, thus explaining the observed competition. This is the first report of a molecular mechanism of action of nonnucleoside inhibitors against a picornaviral RNA-dependent RNA polymerase.
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Du J, Gao S, Luo J, Zhang G, Cong G, Shao J, Lin T, Cai X, Chang H. Effective inhibition of foot-and-mouth disease virus (FMDV) replication in vitro by vector-delivered microRNAs targeting the 3D gene. Virol J 2011; 8:292. [PMID: 21663611 PMCID: PMC3315795 DOI: 10.1186/1743-422x-8-292] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2011] [Accepted: 06/10/2011] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Foot-and-mouth disease virus (FMDV) causes an economically important and highly contagious disease of cloven-hoofed animals. RNAi triggered by small RNA molecules, including siRNAs and miRNAs, offers a new approach for controlling viral infections. There is no report available for FMDV inhibition by vector-delivered miRNA, although miRNA is believed to have more potential than siRNA. In this study, the inhibitory effects of vector-delivered miRNAs targeting the 3D gene on FMDV replication were examined. RESULTS Four pairs of oligonucleotides encoding 3D-specific miRNA of FMDV were designed and selected for construction of miRNA expression plasmids. In the reporter assays, two of four miRNA expression plasmids were able to significantly silence the expression of 3D-GFP fusion proteins from the reporter plasmid, p3D-GFP, which was cotransfected with each miRNA expression plasmid. After detecting the silencing effects of the reporter genes, the inhibitory effects of FMDV replication were determined in the miRNA expression plasmid-transfected and FMDV-infected cells. Virus titration and real-time RT-PCR assays showed that the p3D715-miR and p3D983-miR plasmids were able to potently inhibit the replication of FMDV when BHK-21 cells were infected with FMDV. CONCLUSION Our results indicated that vector-delivered miRNAs targeting the 3D gene efficiently inhibits FMDV replication in vitro. This finding provides evidence that miRNAs could be used as a potential tool against FMDV infection.
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Affiliation(s)
- Junzheng Du
- State Key Laboratory of Veterinary Etiological Biology, National Foot and Mouth Disease Reference Laboratory, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, China
| | - Shandian Gao
- State Key Laboratory of Veterinary Etiological Biology, National Foot and Mouth Disease Reference Laboratory, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, China
| | - Jihuai Luo
- State Key Laboratory of Veterinary Etiological Biology, National Foot and Mouth Disease Reference Laboratory, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, China
| | - Guofeng Zhang
- State Key Laboratory of Veterinary Etiological Biology, National Foot and Mouth Disease Reference Laboratory, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, China
| | - Guozheng Cong
- State Key Laboratory of Veterinary Etiological Biology, National Foot and Mouth Disease Reference Laboratory, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, China
| | - Junjun Shao
- State Key Laboratory of Veterinary Etiological Biology, National Foot and Mouth Disease Reference Laboratory, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, China
| | - Tong Lin
- State Key Laboratory of Veterinary Etiological Biology, National Foot and Mouth Disease Reference Laboratory, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, China
| | - Xuepeng Cai
- State Key Laboratory of Veterinary Etiological Biology, National Foot and Mouth Disease Reference Laboratory, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, China
| | - Huiyun Chang
- State Key Laboratory of Veterinary Etiological Biology, National Foot and Mouth Disease Reference Laboratory, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, China
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A Tyr residue in the reverse transcriptase domain can mimic the protein-priming Tyr residue in the terminal protein domain of a hepadnavirus P protein. J Virol 2011; 85:7742-53. [PMID: 21593158 DOI: 10.1128/jvi.00482-11] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Hepadnaviruses are the only known viruses that replicate by protein-primed reverse transcription. Beyond the conserved reverse transcriptase (RT) and RNase H domains, their polymerases (P proteins) carry a unique terminal protein (TP) domain that provides a specific Tyr residue, Tyr96 in duck hepatitis B virus (DHBV), to which the first nucleotide of minus-strand DNA is autocatalytically attached and extended by three more nucleotides. In vitro reconstitution of this priming reaction with DHBV P protein and cellular chaperones had revealed strict requirements for the Dε RNA stem-loop as a template and for catalytic activity of the RT domain plus RNA-binding competence of the TP domain. Chaperone dependence can be obviated by using a truncated P protein (miniP). Here, we found that miniP with a tobacco etch virus (TEV) protease cleavage site between TP and RT (miniP(TEV)) displayed authentic priming activity when supplied with α-(32)P-labeled deoxynucleoside triphosphates; however, protease cleavage revealed, surprisingly, that the RT domain was also labeled. RT labeling had identical requirements as priming at Tyr96 and originated from dNMP transfer to a unique Tyr residue identified as Tyr561 in the presumed RT primer grip motif. Mutating Tyr561 did not affect Tyr96 priming in vitro and only modestly reduced replication competence of an intact DHBV genome; hence, deoxynucleotidylated Tyr561 is not an obligate intermediate in TP priming. However, as a first alternative substrate for the exquisitely complex protein-priming reaction, dNMP transfer to Tyr561 is a novel tool to further clarify the mechanism of hepadnaviral replication initiation and suggests that specific priming inhibitors can be found.
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Molecular dynamics simulations of viral RNA polymerases link conserved and correlated motions of functional elements to fidelity. J Mol Biol 2011; 410:159-81. [PMID: 21575642 PMCID: PMC3114172 DOI: 10.1016/j.jmb.2011.04.078] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2010] [Revised: 04/27/2011] [Accepted: 04/30/2011] [Indexed: 02/02/2023]
Abstract
The viral RNA-dependent RNA polymerase (RdRp) is essential for multiplication of all RNA viruses. The sequence diversity of an RNA virus population contributes to its ability to infect the host. This diversity emanates from errors made by the RdRp during RNA synthesis. The physical basis for RdRp fidelity is unclear but is linked to conformational changes occurring during the nucleotide-addition cycle. To understand RdRp dynamics that might influence RdRp function, we have analyzed all-atom molecular dynamics simulations on the nanosecond timescale of four RdRps from the picornavirus family that exhibit 30–74% sequence identity. Principal component analysis showed that the major motions observed during the simulations derived from conserved structural motifs and regions of known function. The dynamics of residues participating in the same biochemical property, for example, RNA binding, nucleotide binding or catalysis, were correlated even when spatially distant on the RdRp structure. The conserved and correlated dynamics of functional structural elements suggest coevolution of dynamics with structure and function of the RdRp. Crystal structures of all picornavirus RdRps exhibit a template–nascent RNA duplex channel too small to fully accommodate duplex RNA. Simulations revealed opening and closing motions of the RNA and nucleoside triphosphate channels, which might be relevant to nucleoside triphosphate entry, inorganic pyrophosphate exit and translocation. A role for nanosecond timescale dynamics in RdRp fidelity is supported by the altered dynamics of the high-fidelity G64S derivative of PV RdRp relative to wild-type enzyme.
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49
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Agudo R, Ferrer-Orta C, Arias A, de la Higuera I, Perales C, Pérez-Luque R, Verdaguer N, Domingo E. A multi-step process of viral adaptation to a mutagenic nucleoside analogue by modulation of transition types leads to extinction-escape. PLoS Pathog 2010; 6:e1001072. [PMID: 20865120 PMCID: PMC2928812 DOI: 10.1371/journal.ppat.1001072] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2010] [Accepted: 07/26/2010] [Indexed: 01/18/2023] Open
Abstract
Resistance of viruses to mutagenic agents is an important problem for the development of lethal mutagenesis as an antiviral strategy. Previous studies with RNA viruses have documented that resistance to the mutagenic nucleoside analogue ribavirin (1-β-D-ribofuranosyl-1-H-1,2,4-triazole-3-carboxamide) is mediated by amino acid substitutions in the viral polymerase that either increase the general template copying fidelity of the enzyme or decrease the incorporation of ribavirin into RNA. Here we describe experiments that show that replication of the important picornavirus pathogen foot-and-mouth disease virus (FMDV) in the presence of increasing concentrations of ribavirin results in the sequential incorporation of three amino acid substitutions (M296I, P44S and P169S) in the viral polymerase (3D). The main biological effect of these substitutions is to attenuate the consequences of the mutagenic activity of ribavirin —by avoiding the biased repertoire of transition mutations produced by this purine analogue—and to maintain the replicative fitness of the virus which is able to escape extinction by ribavirin. This is achieved through alteration of the pairing behavior of ribavirin-triphosphate (RTP), as evidenced by in vitro polymerization assays with purified mutant 3Ds. Comparison of the three-dimensional structure of wild type and mutant polymerases suggests that the amino acid substitutions alter the position of the template RNA in the entry channel of the enzyme, thereby affecting nucleotide recognition. The results provide evidence of a new mechanism of resistance to a mutagenic nucleoside analogue which allows the virus to maintain a balance among mutation types introduced into progeny genomes during replication under strong mutagenic pressure. Viruses that have RNA as genetic material include many important human, animal and plant pathogens. A new strategy against RNA viruses consists in using mutagenic nucleotides. The objective is to provoke an excessive number of mutations, to deteriorate the viral functions to the point that the virus can not survive. One of the mutagens used in research on lethal mutagenesis is ribavirin, extensively employed in clinical practice. Unfortunately, viral mutants that are resistant to ribavirin have been selected, thus facilitating escape from lethal mutagenesis. Here we describe a new mechanism by which foot-and-mouth disease virus (FMDV) can become resistant to ribavirin. Amino acid changes in the viral polymerase, selected by ribavirin, are able to modify the types of mutations produced in the presence of ribavirin. Biochemical data indicate that the alteration of the enzyme changes the pairing behavior of ribavirin, avoiding the production of an excess of some types of mutations, supporting the hypothesis that an unbalanced mutation repertoire is detrimental to the virus. Thus, this new mechanism of resistance to ribavirin is based not as much in limiting the number of mutations in the virus genetic material but in ensuring an equilibrium among different types of mutations that favors viral survival.
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Affiliation(s)
- Rubén Agudo
- Centro de Biologia Molecular “Severo Ochoa” (CSIC-UAM), Cantoblanco, Madrid, Spain
| | - Cristina Ferrer-Orta
- Institut de Biologia Molecular de Barcelona (CSIC), Parc Científic de Barcelona, Barcelona, Spain
| | - Armando Arias
- Centro de Biologia Molecular “Severo Ochoa” (CSIC-UAM), Cantoblanco, Madrid, Spain
| | | | - Celia Perales
- Centro de Biologia Molecular “Severo Ochoa” (CSIC-UAM), Cantoblanco, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Barcelona, Spain
| | - Rosa Pérez-Luque
- Institut de Biologia Molecular de Barcelona (CSIC), Parc Científic de Barcelona, Barcelona, Spain
| | - Nuria Verdaguer
- Institut de Biologia Molecular de Barcelona (CSIC), Parc Científic de Barcelona, Barcelona, Spain
| | - Esteban Domingo
- Centro de Biologia Molecular “Severo Ochoa” (CSIC-UAM), Cantoblanco, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Barcelona, Spain
- * E-mail:
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Wu Y, Lou Z, Miao Y, Yu Y, Dong H, Peng W, Bartlam M, Li X, Rao Z. Structures of EV71 RNA-dependent RNA polymerase in complex with substrate and analogue provide a drug target against the hand-foot-and-mouth disease pandemic in China. Protein Cell 2010; 1:491-500. [PMID: 21203964 DOI: 10.1007/s13238-010-0061-7] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2010] [Accepted: 04/30/2010] [Indexed: 12/27/2022] Open
Abstract
Enterovirus 71 (EV71), one of the major causative agents for hand-foot-and-mouth disease (HFMD), has caused more than 100 deaths among Chinese children since March 2008. The EV71 genome encodes an RNAdependent RNA polymerase (RdRp), denoted 3D(pol), which is central for viral genome replication and is a key target for the discovery of specific antiviral therapeutics. Here we report the crystal structures of EV71 RdRp (3D(pol)) and in complex with substrate guanosine-5'-triphosphate and analog 5-bromouridine-5'-triphosphate best to 2.4 Å resolution. The structure of EV71 RdRp (3D(pol)) has a wider open thumb domain compared with the most closely related crystal structure of poliovirus RdRp. And the EV71 RdRp (3D(pol)) complex with GTP or Br-UTP bounded shows two distinct movements of the polymerase by substrate or analogue binding. The model of the complex with the template:primer derived by superimposition with foot-and-mouth disease virus (FMDV) 3D/RNA complex reveals the likely recognition and binding of template:primer RNA by the polymerase. These results together provide a molecular basis for EV71 RNA replication and reveal a potential target for anti-EV71 drug discovery.
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Affiliation(s)
- Yang Wu
- National Laboratory of Macromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
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